Sarcoid polyneuropathy masquerading as chronic inflammatory demyelinating polyneuropathy

Area of Science:

• Neurology
• Immunology
• Pathology

Background:

• Sarcoid polyneuropathy is an uncommon neurological disorder and a potential initial manifestation of sarcoidosis.
• It presents with diverse clinical features, making diagnosis difficult.

Observation:

• A 36-year-old male with a decade-long diagnosis of sensory-predominant chronic inflammatory demyelinating polyneuropathy (CIDP) showed limited response to immunosuppressants.
• He presented with gait disturbance and muscle cramps, with electrodiagnostic findings suggesting chronic demyelinating polyradiculoneuropathy and conduction blocks.

Findings:

• Systemic symptoms emerged, and tissue biopsies confirmed granulomatous disease, leading to a revised diagnosis of sarcoid polyneuropathy.
• The patient experienced symptom improvement following steroid therapy.

Implications:

• Sarcoid polyneuropathy diagnosis requires a high index of suspicion in atypical neuropathy cases.
• Nerve and muscle biopsies are vital for diagnosing this treatable condition, especially with refractory symptoms or systemic signs.